1. Field of the Invention
The present invention is related to an automatic bending-angle changing structure for an umbrella, and especially to such a structure in which an upper and a lower sleeve are respectively fitted in a turning cylinder and a turner bracket to allow the two to turn relatively to each other and to allow the umbrella to open and collapse by means of a reel and a fine rope through controlling a runner, a pulley set and a hinge set. In this mode, the umbrella is convenient for manipulating in bending. Such structure suits big umbrellas or similar articles; the umbrellas can have bending angles of their shafts changed.
2. Description of the Prior Art
Since big umbrellas were widely used, sun-shading function of them has been highly thought of. In coincidence with the angles of sun shining to effectively shade direct incidence of sunshine, various big umbrellas are produced in large amount in the markets.
However, a positioning device for most conventional bending connectors of big umbrellas as shown in FIG. 1 is comprised mainly of: a bending body provided on the lower end thereof with two feet with bevel end faces which form therebetween a gap, a bevel stop surface is provided at the bottom of the gap; a round hole is provided on both the two feet. A connector for connecting stretchers is provided with a top protrusion also having a round holes thereon. An elastic spring loaded pin and a movable collar are provided at the junction of the bending body and the connector for connecting stretchers; by extending the spring loaded pin through the abovementioned round holes, and slipping of the movable collar over the junction, when in bending the umbrella, the bevel stop surface can maintain the bending angle and positioning. However, it only gets one bending angle, but can not coincide with the angles of sun shining; and by the fact that the weight of the umbrella is quite large, the umbrella must be manipulated with two hands and is subjected to the danger of tipping, thereby, the conventional structure is undesired.
Another conventional structure is shown in FIG. 2 which is comprised mainly of: an upper convex connector, a lower concave connector, a positioning rod, a spring cotter and a spring. The upper convex connector is provided on a flat upper engaging end portion thereof with a positioning flange; the lower concave connector is provided on the inner sides of the top engaging ribs thereof with arciform recesses for engaging and limiting to prevent overly large bending angles, and the bending angles can be predetermined. Thereby, practicality of convenient engaging and positioning in bending can be obtained. However, such a positioning device for bending connectors of big umbrellas can only render the lower concave connectors provided on the inner sides of the top engaging ribs thereof with arciform recesses for engaging and limiting, direction variations are few, and each time when it is bent, the positioning rod must be pulled out and the upper convex connector has to be supported with one hand; and by the fact that the weight of the umbrella supported by the upper convex connector is quite large, the umbrella must be manipulated with two hands, an operator thereby is subjected to uneasy holding and damaging his hands. The conventional structure is uneasy for manipulation and can not completely shade direct incidence of sunshine as well as is subjected to damaging hands of an operator; it is still undesired.
In view of the above statement, the inventor desired to avoid the abovementioned defects resided in conventional structures, and expected to provide a structure which is able to shade direct sunshine irrespective of the angle of incidence of sunshine, and is convenient and power saving for manipulation; after hard study and tests, the present invention is provided.
The main object of the present invention is to provide an automatic bending angle changing structure for an umbrella, the structure on the shaft of the umbrella is apparently identical to a normal shaft of the umbrella, while the shaft is bendable and suits various umbrellas.
The secondary object of the present invention is to provide an automatic bending angle changing structure for an umbrella, by which a user needs only to rotate a reel with one hand to open the folded umbrella easily, and the shaft of the umbrella can be bent for various bending angles, these are convenient for manipulation, and thereby convenience of use of umbrellas can be increased.
To get the above stated objects, the present invention is comprised of an upper and a lower sleeve, a pulley holding rod, a turning cylinder, a turner bracket, a pulley set and a hinge set. The pulley set is mounted on the pulley holding rod which then is extended into the upper sleeve, and the turning cylinder is slipped over the upper sleeve; the lower end of the pulley holding rod is slipped thereover with the turning cylinder and is pin connected with the upper end of the hinge set, the lower end of the hinge set is pin connected with the turning cylinder and the turner bracket; thereby a linkage is formed. The lower end of the turner bracket is slipped into the lower sleeve which is provided thereon with the reel; a fine rope is wound on the pulley set by means of the reel to move the runner, the turning cylinder and the turner bracket, thereby the umbrella can have variation in opening, collapsing and bending. Thereby the structure is convenient and power saving for manipulation, and can have bending angles of the shaft of the umbrella changed to shade sunshine, and thereby practicality and convenience of the umbrella is increased.
The present invention will be apparent in its structure and features after reading the detailed description of the preferred embodiment thereof in reference to the accompanying drawings.